speedometer problem

[yuma]

Don't know if the motorhome was protesting heading north or not but noticed after a fueling stop that the speedometer on our 2000 allegro bay with about 40000 mi on it was not working.Later on after about 250 mi. I looked down and lo and behold it was working again!And has been working flawlessly the next 1200 or so miles.Any ideas as to what to check????

[Hooligan]

yuma: Don't know your MH or chassis, but the VDC (vehicle data computer) on Freightliner chassis has shown similiar problems. Often a poor connection of the plugs at the VDC. The VDC feeds the info to the dash gauges. Good discussion here.
Speedometer Still Fails

If you don't have a Freightliner, post particulars on your rig and someone here may be able to help.

[yuma]

Should have said its a Ford chassis with a v-10.Sorry for the confusion.

[J Walker]

You still likely have an electrical connection to the dash that gives the signal to all the dash gauges including the speedometer. Check the plugs. You can delve into the Ford chassis but from others I have learned that there are several plugs you should look besides the on to the speedometer under the dash.

[Fred B.]

When speedometer quits & overdrive light flahes thats a speedsensor failure or loose connection to same. Shutting down & restart will clear it.

[SRT]

Quote:

Originally Posted by Fred B. When speedometer quits & overdrive light flahes thats a speedsensor failure or loose connection to same. Shutting down & restart will clear it.

That's true. As I understand, there is a kit by Ford that installs an extra ground to prevent this problem.

[John-D]

Well, I often say we motor homers have a few screws loose (Or connections loose)

This one will most likely be on a ground lead, but could be most anywhere on the speed sensor line.

["007"]

Make sure you have good ground connection, as some have said, run a new one its easier.

[PanJH]

Look at ( clean) the connector on the speed sensor on the rear differential. It's on the upper driver's side of the rear end pumkin

[atomic98]

on my 1998 safari, the speedometer needle is pegged, and stays there. When the key turns on, the needle mooves, but that is it. Before, when the key was turned on, the needle went from 0 to pegged, then back to 0. It worked fine, up until right before it quit...at that time it was reading 30mph while I was running 60. Any ideas?

[isa]

When my Ford v-10 speedometer started acting up I replaced the vehicle speed sensor VSS that is located on the upper left hand side of the rear differential. The Ford Motorcraft part number is BRAB - 130 or F85Z-2L373-AC and costs about $25. On mine it was held on by a 10mm bolt. Be careful when you try to take the electrical plug off. I broke one of the holding clips and had to use the old faithfull duct tape when I put the new sensor back on.